The insecticide containing $99\%$ $\gamma-isomer$ of benzene hexachloride is known as

Which of the following chloro-compounds shows complete inversion of configuration during a reaction?

What is retention and inversion of configuration? Explain with suitable examples.

Which of the following can be used as the halide component for Friedel-Crafts reaction?

Which of the following statements is correct for the reactivity in $S_N2$ reaction?

Consider the following reaction sequence:
$Cyclohexylidene-methane$ $\xrightarrow[CH_3OH]{Br_2} A$ $\xrightarrow{KCN} B$
Identify the correct structures for $A$ and $B$ from the given options:
$A$ is:
$A) \text{ 1-(bromomethyl)-1-methoxycyclohexane}$
$B) \text{ 1-(methoxymethyl)-1-bromocyclohexane}$
$B$ is:
$C) \text{ 1-(bromomethyl)-1-methoxycyclohexane}$
$D) \text{ 1-(cyanomethyl)-1-methoxycyclohexane}$